The present invention relates generally to a filter for cleaning the water in an aquarium used to keep fish. More particularly this invention relates to a filter for cleaning aquarium water which is completely submerged in the water of the aquarium when in use, and draws water into and through a cavity in the filter housing. This filter cavity is filled with a filtering material in order to trap debris and particulate matter present in the aquarium water.
The present invention finds use in cleaning different types of debris material from the water of an aquarium used to house fish. It is suited for use in the general upkeep of the aquarium by the home aquarium hobbyist, by the researcher in a laboratory setting, or in similar circumstances.
A water filtering system is an essential component in order to maintain fish in an aquarium setting. In the home hobbyist aquarium, laboratory aquarium, or in similar settings where low volume tanks of about 5 to 40 gallons are used, it is customary to filter the aquarium water with a filter which sits in the fish tank, fully submerged in the water. Filtering is accomplished by forcing water into the body cavity of the filter through a system of slits and/or holes and out of the body cavity through a second system of slits and/or holes. The filter cavity is filled with a filtering material which entraps the debris and other particulate matter commonly found in fish tank water.
A common means of forcing the water into and through the filtering material containing cavity is by employing a bubbling mechanism attached to an air source outside of the fish tank by a length of air hose or air tubing. This causes bubbles to form at a low point in a chamber attached to the filter cavity by a common passageway. When the formed bubbles rise toward the surface of the aquarium water, a current is formed which draws water from the aquarium into the filter cavity. The water passes through filtering material in the filter cavity and then out of the filter cavity following the current established by the bubbles. This means of drawing the water through the filter cavity also provides desired aeration to the aquarium water which is beneficial for the maintenance of the fish.
The above described filtering system is know in the art as a corner filter, or box type filter. In using these filters two major drawbacks are encountered. First of all, it is extremely difficult to position the filter in the fish tank in a manner so that it remains submerged in the water for use as a filter. There is a tendency for the filter to rise up to the top of the tank if not securely positioned for use, especially when air is blown into the system to form the necessary water current. In order to solve this problem it is common to place the filter cavity upon a base unit which may be buried under the bottom material of the aquarium. This bottom material, often a gravel type substance, holds the base and filter unit under the aquarium water and prevents it from floating to the surface.
A major problem is encountered when the filter unit is kept in position by this method of burying the base under the bottom gravel type material. The filtering material inside of the filter cavity must be changed on a regular basis in order for it to function properly in cleaning the fish tank water. When the filtering material is changed the base of the filter must be pulled out of the gravel material, and the entire filter must be removed from the fish tank. This often causes the aquarium water to become excessively cloudy. Further, the pulling out of the filter unit and base often disrupts the other items positioned in the aquarium. When the filtering material is changed the filter must then be fully repositioned in the aquarium causing further disruption and clouding.
It is also known in the art to position a box or corner type filter within the aquarium by attaching it to the wall of the aquarium. Often suction cups are used to attach the filter to the wall of the aquarium. While less disruption is caused when the filtering material used in this type of filter is changed, the entire filter must be removed from the tank. Again, the filter must be fully repositioned in the tank after the filtering material is changed. In order to clean the filter cavity the air tubing from the outside air source must be disconnected from the filter. Repositioning the filter in the tank and reconnecting the tubing can be difficult, messy, and often results in disruption to the fish tank.
A second drawback encountered with the use of a corner or box type filter also involves changing the filtering material. Filtering material generally used in these types of filters consist of two components. There is a coarse granular material, such as charcoal, or activated carbon which is suitable for absorbing the debris. Also commonly used is a floss material such as glass wool, or polyester floss, which can trap the debris. When these materials are wet and dirty with fish tank debris they are difficult to handle without causing a great mess. Particularly, the coarse material sticks to the walls of the filter cavity and is difficult to remove.
To remedy this drawback involving the changing of the filtering material it has been known in the art to form a cartridge with the coarse filtering material on the inside, and the floss material forming the outer walls of the cartridge. The filter cartridge and the cavity of the filter are formed in such a manner so that the filter cartridge may be placed into the filter cavity to perform the filter function, and easily removed from the cavity so that it can be replaced with a clean cartridge. The slit and/or hole system and the means of drawing the water through the filter cavity are adapted so that the water passes through the filter cartridge. The filter cartridge system allows for efficient cleaning of the aquarium water, but allows the filtering material, and particularly the coarse material, to be quickly and easily replaced.
The aquarium filter of the present invention is of the type which is attached to the side wall of the aquarium preferably in the corner of the tank. The invention defined by the claims is directed to the problems relating to repositioning of the filter and reconnecting of the filter tubing which are encountered in the use of known filter units of this type. The present filter unit is provided with a sleeve unit which may be attached to the inside wall of the aquarium. The walls of the sleeve unit when in contact with the back wall of the filter cavity housing forms a chamber for the passage of the water and air bubbles. This sleeve unit has attached thereto a mechanism for producing the air bubbles necessary to establish the water current. The air tube from the outside air source is attached to the bubbling mechanism in the sleeve unit. The filter cavity housing is removably attached to the sleeve unit. When the sleeve unit is attached to the wall of the aquarium the filter cavity is secured in position on the inside of the aquarium by attaching the filter cavity housing to the sleeve unit. The filter cavity may be removed from the aquarium in order to change the filtering material by simply detaching the filter cavity housing from the sleeve unit. The sleeve unit remains securely in position on the wall of the aquarium. It is not necessary to reposition the sleeve unit in the tank. Therefore, when the filter material requires changing the filter cavity may be quickly and easily removed from the sleeve unit and then reattached to the sleeve unit which remains attached to the aquarium wall. Because of this there is little or no disruption to the aquarium, and excessive clouding does not occur. Also, since the bubbling mechanism and air tubing are positioned on the sleeve unit the attachment to the outside air source may be maintained during the operation of changing the filter material in the filter cavity. By eliminating the necessity to disconnect, and reconnect the air tubing, the filter material may be changed in a quick, easy and efficient manner with a minimum of disruption to the aquarium.
Further, a preferred embodiment of the present invention incorporates, in addition to the above described sleeve mounting unit, the ability to use a cartridge filter material. The filter cavity is formed in such a manner so that it can accept a cartridge and so that the water is drawn through the cartridge when the filter is in use. By the combination of these two features the present invention forms an extremely effective filtering system which allows for quick and efficient changing of the filtering material. When the filter cavity housing is disconnected from the sleeve unit, the soiled filtering material cartridge may be shaken out of the filter cavity without requiring the hobbyist to contact the soiled cartridge. The filter of this invention thereby provides for the proper maintenance of clean aquarium water with a minimum of mess, effort and disruption of the aquarium.